Same word as over-stepping:

abjure, breach, break, combat, conflict with, counteract, cross, defy, disaffirm, disobey, encroach, exclude, fight, gainsay, hinder, impugn, infract, infringe, interfere, interpose, intrude, negate, offend, oppose, overstep, refute, reject, repudiate, resist, spurn, thwart, transgress, traverse, trespass, violate